From the Archives of the AFIP: Intralobar Sequestration

Radiologic-Pathologic Correlation

Abstract Introduction Postulated Pathogenesis Clinical Characteristics

Pathologic Features Histologic Features Radiologic Appearance

Therapy And Prognosis Conclusions Source Information References

Pathologic Features

The vast majority of cases of intralobar sequestration (98%) are located within the lower lobes, and the lesion is slightly more common (55% 64% of cases) in the left lung than in the right lung (1,2,5,10). At gross inspection, the visceral pleura overlying the sequestered segment appears thickened by fibrosis and has multiple irregular, cordlike adhesions to adjacent structures, including the mediastinum, diaphragm, and parietal pleura (Figure 5a) (1,2). On cut specimens, a segment of dense fibrotic and consolidated parenchyma that often contains multiple cysts filled with fluid or a thick gelatinous material is seen (Figure 5b, Figure 6, Figure 7a) (2,10). Infected purulent material may be found within the cysts (5,8). The cystic spaces may be arranged in the configuration of ectatic bronchi, and some authors propose that the cysts develop as a result of persistent mucous secretion into obstructed bronchi (5,26).

The lesion is typically surrounded by nonsequestered, otherwise normal lung tissue (Figure 5b, Figure 7a) (2). The incomplete, partially fibrous boundary between sequestered and normal lung tissue has long been considered to be the route of collateral air drift into the lesion (30), although Stocker and Malczak (10) propose that air within anintralobar sequestration represents either incomplete bronchial obstruction or partial recanalization of previously obstructed bronchi in the setting of chronic infection.

Abstract Introduction Postulated Pathogenesis Clinical Characteristics

Pathologic Features Histologic Features Radiologic Appearance

Therapy And Prognosis Conclusions Source Information References